The present invention relates to an improved polyarylene sulfide resin composition and a process for the preparation of the same. More particularly, the invention relates to a polyarylene sulfide resin composition having excellent impact resistance and heat resistance which is prepared by blending a resin component comprising a polyarylene sulfide resin and a polyamide resin with a specific compound and, if necessary, a radical initiator and melt-kneading the obtained mixture.
Recently a thermoplastic resin which has high heat resistance and chemical resistance and excellent flame retardance has been demanded as the material of construction for components of electrical or electronic appliances, automobile parts and chemical instruments.
A polyarylene sulfide resin represented by polyphenylene sulfide is one of the resins satisfying this demand. Polyarylene sulfide is relatively inexpensive for its physical properties, so that the demand therefor has increased. However, a polyphenylene sulfide resin has a significant disadvantage in that it is poorer in ductility and is more brittle than other engineering plastics such as nylon, polycarbonate and polybutylene terephthalate.
The addition of a fibrous reinforcement such as glass fiber or carbon fiber or other filler has been known as a means for remarkably improving the resin with respect to various performances such as strengths, stiffness, toughness and heat resistance to overcome the above disadvantage. However, a composition prepared by adding such a reinforcement to a polyarylene sulfide resin is still inferior to other engineering plastics with respect to toughness, so that the application of the composition in various fields is restricted, even though the composition has excellent chemical resistance, heat resistance and flame retardance.
The inventors of the present invention have found that a composition prepared by adding a silane compound having an alkoxysilyl group to a resin component comprising a polyarylene sulfide resin and a polyamide resin exhibits improved impact resistance. As a result, they filed Japanese Patent Application Nos. 320140/1989, 44140/1990, 110839/1990 and U.S. patent application Ser. No. 623,028, filed Dec. 6, 1991 on the basis of this finding. Although the compositions according to these inventions have excellent toughness and impact resistance, the melt viscosity thereof tends to increase causing difficulties during injection molding. Accordingly, a further improvement in this respect has been needed.